/* * NV-RAM memory access on autcpu12 * (C) 2002 Thomas Gleixner (gleixner@autronix.de) * * $Id: autcpu12-nvram.c,v 1.9 2005/11/07 11:14:26 gleixner Exp $ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/ioport.h> #include <linux/init.h> #include <asm/io.h> #include <asm/sizes.h> #include <asm/hardware.h> #include <asm/arch/autcpu12.h> #include <linux/mtd/mtd.h> #include <linux/mtd/map.h> #include <linux/mtd/partitions.h> static struct mtd_info *sram_mtd; struct map_info autcpu12_sram_map = { .name = "SRAM", .size = 32768, .bankwidth = 4, .phys = 0x12000000, }; static int __init init_autcpu12_sram (void) { int err, save0, save1; autcpu12_sram_map.virt = ioremap(0x12000000, SZ_128K); if (!autcpu12_sram_map.virt) { printk("Failed to ioremap autcpu12 NV-RAM space\n"); err = -EIO; goto out; } simple_map_init(&autcpu_sram_map); /* * Check for 32K/128K * read ofs 0 * read ofs 0x10000 * Write complement to ofs 0x100000 * Read and check result on ofs 0x0 * Restore contents */ save0 = map_read32(&autcpu12_sram_map,0); save1 = map_read32(&autcpu12_sram_map,0x10000); map_write32(&autcpu12_sram_map,~save0,0x10000); /* if we find this pattern on 0x0, we have 32K size * restore contents and exit */ if ( map_read32(&autcpu12_sram_map,0) != save0) { map_write32(&autcpu12_sram_map,save0,0x0); goto map; } /* We have a 128K found, restore 0x10000 and set size * to 128K */ map_write32(&autcpu12_sram_map,save1,0x10000); autcpu12_sram_map.size = SZ_128K; map: sram_mtd = do_map_probe("map_ram", &autcpu12_sram_map); if (!sram_mtd) { printk("NV-RAM probe failed\n"); err = -ENXIO; goto out_ioremap; } sram_mtd->owner = THIS_MODULE; sram_mtd->erasesize = 16; if (add_mtd_device(sram_mtd)) { printk("NV-RAM device addition failed\n"); err = -ENOMEM; goto out_probe; } printk("NV-RAM device size %ldKiB registered on AUTCPU12\n",autcpu12_sram_map.size/SZ_1K); return 0; out_probe: map_destroy(sram_mtd); sram_mtd = 0; out_ioremap: iounmap((void *)autcpu12_sram_map.virt); out: return err; } static void __exit cleanup_autcpu12_maps(void) { if (sram_mtd) { del_mtd_device(sram_mtd); map_destroy(sram_mtd); iounmap((void *)autcpu12_sram_map.virt); } } module_init(init_autcpu12_sram); module_exit(cleanup_autcpu12_maps); MODULE_AUTHOR("Thomas Gleixner"); MODULE_DESCRIPTION("autcpu12 NV-RAM map driver"); MODULE_LICENSE("GPL");